Field of the Technology
The disclosure relates to the field of endoscopic probes using ultrasound and optical coherent tomography.
Description of the Prior Art
Gastrointestinal (gastrointestinal) cancers causes more than 140,000 deaths with more than 290,000 new cases in the United States in 2014. Esophageal cancer is one of most common gastrointestinal cancer diseases with a five-year survival rate only 16%. Esophageal adenocarcinoma is developed from the gastro esophageal reflux disorder of Barrett's esophagus (BE). The unique characteristic of BE is abnormal replacement of squamous epithelium with columnar epithelium. The detection of preceding dysplasia is believed to reduce the risk of adenocarcinoma. Colorectal cancer is another common gastrointestinal disease with high morbidity and mortality rates. Although most colorectal cancers arise from adenomatous polyps that are detectable using conventional endoscopy, many flat (non-polypoid) lesions, up to 50%, are missed during routine examinations.
The standard procedure to facilitate early diagnosis of common gastrointestinal cancer diseases is to perform histological analysis based tissue biopsy in abnormal regions that can be identified by endoscopy, or random biopsies over a large area (such as entire length of BE or colon). Besides inadequate sampling, the problem of early detection of dysplasia in the gut is exacerbated in the presence of chronic inflammatory conditions such as esophagitis, since early-stage lesions are difficult to distinguish from inflamed gastrointestinal mucosa by the endoscopist.
In addition to the most common upper digestive track cancer diagnosis, such as esophagus cancer, one specific clinical problem to be solved is the diagnosis of cholangiocarcinoma (CCA). CCA is an epithelial cancer of bile ducts with features of cholangiocyte differentiation. CCA is the second most common primary hepatic malignancy. The patient incidence in the United States is 1.77/100,000 and this number is increasing in Western countries. Advanced CCA has a devastating prognosis, with a median survival of <24 months. Hepatobiliary malignancies account for 13% of the 7,6 million annual cancer-related deaths worldwide, and CCA accounts for 10% to 20% of the deaths from hepatobiliary malignancies. The market size of diagnosing CCA is around 0.5˜1 billion dollars.
The conventional standard for diagnosing CCA is a bile duet biopsy technique, which uses a tiny catheter-based brush to be advanced into the bile duct to scrape the surface of duct wall, in order to harvest cells from the lesion area for cytological analysis. This crude approach is very invasive and harmful to the patients and the accuracy is still below 50%. Moreover, the biopsy approach only allows the clinician to harvest cells on the inner surface of bile duct, and has no diagnosing ability for tissues several millimeters beyond the epithelium of the bile duet. These serious limitations of the current clinical practice for diagnosis of CCA demonstrate a great, need for developing more advanced imaging technologies with higher sensitivity and safety.
Another specific problem to be solved is the diagnosis of cystic neoplasms of the pancreas. Cystic neoplasms of the pancreas include serous cystic tumors, mucinous cystic neoplasms, solid pseudopapillary neoplasms, cystic islet cell tumors, and intraductal papillary mucinous neoplasms of the pancreas (IPMNs). IPMNs have also been referred to as mucinous duct ectasias and intraductal papillary mucinous tumors. IPMNs are potentially malignant intraductal epithelial neoplasms that are grossly visible (>1 cm) and are composed of mucin-producing columnar cells. At this time, many patients undergo surgical resection of pancreatic cysts. Classification and thus prognosis of pancreatic cysts are currently best made at the time of surgical resection as there are yet no imaging characteristics or cyst fluid tumor markers sensitive and specific enough on which to base such decisions. A technology is needed that would provide the physician with a preoperative diagnosis on which to base decisions as the basis of whether to operate or not. This could have a profound clinical as well as economic impact.